Description: Learn how to multiply (9 × 10^9) × [-2 × 10^(-3)]. So the first thing I would want to do is let's just change the order of multiplication. Let's multiply the nine and the negative two first and then we can multiply the 10 to the ninth and 10 to the negative third power. Nine times negative two times 10 to the ninth power.*Teacher Advisor is 100% free.